The present invention relates to novel substances capable of inhibiting serotonin release from platelets and/or platelet aggregation which are produced by a microorganism belonging to the genus Sporothrix, a process for preparing the same and a pharmaceutical composition containing the same.
Products of a large number of microorganisms obtained from nature have been studies with a view to providing useful novel physiologically active substances which can be used as pharmaceuticals or intermediates therefor. As a result, it has been found that physiologically active substances capable of inhibiting serotonin release from platelets and/or platelet aggregation are produced in the culture of a newly isolated microorganism. After isolation and purification of the substances from the culture, their physicochemical properties have been investigated, whereby the substances have been found to be novel physiologically active substances. The substances are hereinafter referred to as KS-501 and KS-502.
As the substances capable of inhibiting serotonin release from platelets or platelet aggregation which are produced by microorganisms, the following compounds have been reported.